FHIR and SMART on FHIR
EVAL's EHR integrations are built on two open healthcare interoperability standards: FHIR (Fast Healthcare Interoperability Resources) and SMART on FHIR. These standards allow EVAL to communicate securely with your electronic health record system without custom point-to-point integrations — the same connection architecture works across Epic, Cerner, athena, and every other supported EHR.
Understanding these standards helps your IT team evaluate EVAL's integration requirements, configure your EHR's FHIR capabilities, and troubleshoot connection issues. If you're a clinician or researcher who just wants to use the integration, you don't need to read this page — the Creating connections and Managing connections guides cover everything you need to get started.
What is FHIR?
FHIR (Fast Healthcare Interoperability Resources) is a standard developed by HL7 International for exchanging healthcare data between systems. It defines a common language — a set of resources — that represent clinical concepts like patients, observations, conditions, medications, and encounters. When EVAL requests patient data from your EHR, both systems speak FHIR, so the data arrives in a predictable, structured format regardless of which EHR vendor you use.
EVAL uses FHIR R4, the current production release of the standard and the version mandated by the US Office of the National Coordinator for Health IT (ONC) for certified health IT modules. All eight supported EHR systems in EVAL implement FHIR R4 endpoints, which is why the connection experience is consistent across vendors.
In practical terms, FHIR means that when EVAL synchronizes a patient chart from your EHR, it receives standardized resources — patient demographics, clinical observations, diagnoses, and other relevant data — that EVAL can reliably interpret and display. Your EHR team doesn't need to build a custom export for EVAL; they just need to ensure the FHIR R4 endpoint is accessible and properly configured.
What is SMART on FHIR?
SMART on FHIR (Substitutable Medical Applications, Reusable Technologies) is a security and authorization layer built on top of FHIR. While FHIR defines what data can be exchanged, SMART on FHIR defines who can access it and how they get permission.
SMART on FHIR handles three critical functions for EVAL's integrations:
Authentication — When a clinician launches EVAL from within the EHR (via EHR Launch mode), SMART on FHIR manages the identity handoff. The EHR tells EVAL who the clinician is and which patient they're viewing, so EVAL can open directly to the right context without requiring a separate login.
Authorization — SMART on FHIR controls what data EVAL can access. Your EHR administrator configures the specific scopes (permissions) that EVAL receives — typically read access to patient demographics, clinical observations, and conditions. EVAL only sees the data your organization has explicitly authorized.
App launch — The SMART App Launch framework defines how EVAL starts from within an EHR session. When a clinician clicks the EVAL link in Epic, Cerner, or another EHR, the SMART protocol orchestrates the secure handoff — passing the current patient context to EVAL while maintaining the clinician's authenticated session.
EVAL uses SMART on FHIR v1, which is the widely adopted version supported across all major EHR platforms.
How EVAL uses these standards
Each connection mode leverages FHIR and SMART on FHIR differently:
EHR Launch and SSO connections use the full SMART App Launch flow. When a clinician opens EVAL from within the EHR, the SMART protocol authenticates the user, passes the patient context, and grants EVAL time-limited access to read clinical data. This all happens in the background — the clinician sees a seamless transition from the EHR to EVAL with the correct patient already loaded.
Background Service connections use SMART Backend Services authorization (also known as the SMART system-level authorization flow). Instead of authenticating an individual clinician, the connection authenticates EVAL itself as a trusted service using a client credential. This allows EVAL to access patient data for bulk import and patient sync operations without requiring a user to be logged in — essential for keeping patient records synchronized overnight or during off-hours.
During the discovery step of connection creation, EVAL queries your EHR's FHIR capability statement — a standardized document that every FHIR server publishes describing what it can do. This tells EVAL which FHIR resources are available, which SMART authorization flows are supported, and whether the server meets the requirements for the connection mode you've selected.
What your IT team needs to know
If you're configuring EVAL's EHR integration for your organization, here are the key requirements your EHR technical team should be aware of:
FHIR R4 endpoint — Your EHR must expose a FHIR R4-compliant endpoint. This is the Service Base URL you enter during connection setup. Most major EHR systems have FHIR R4 enabled by default, but some require activation through the EHR's administration console.
SMART on FHIR v1 support — Your EHR's FHIR endpoint must support SMART on FHIR v1 for authentication and authorization. For EHR Launch connections, this means supporting the SMART App Launch Framework. For Background Service connections, this means supporting SMART Backend Services.
Client registration — EVAL needs to be registered as an authorized application in your EHR's FHIR configuration. This typically involves creating a client ID (and sometimes a client secret) through your EHR vendor's developer portal or application registration process — for example, Epic's App Orchard, Cerner's Code Console, or athena's Developer Portal.
Network accessibility — Your EHR's FHIR endpoint must be reachable from EVAL's servers. For Background Service connections that synchronize data automatically, this means the endpoint needs to be available around the clock, not just during business hours.
FHIR Bulk Data Export (optional) — If you plan to use bulk import to transfer large batches of patient data, your EHR must support the FHIR Bulk Data Export specification. This is a requirement for Background Service connections that need to import an entire patient population. Not all EHR configurations enable bulk export by default — check with your vendor.
Further reading
EVAL's integration architecture follows published open standards. If your IT team wants to understand the specifications in detail, the authoritative sources are:
- HL7 FHIR R4 — the data exchange standard that defines how clinical data is structured and transmitted
- SMART App Launch Framework — the specification for launching applications from within an EHR with patient context
- SMART Backend Services — the specification for system-to-system authorization used by Background Service connections
- FHIR Bulk Data Export — the specification for efficient large-scale data transfer
These standards are maintained by HL7 International and the SMART Health IT project. Your EHR vendor's technical documentation will describe how they implement these standards in their specific system.